Artifacts are a common occurrence during EEG recording and typically do not present a significant challenge to skilled neurophysiologists. However, in rare instances physiological electroencephalographic activity may closely mimic artifacts, potentially leading to missed or significantly delayed diagnosis. We report a case involving highly focal electrographic seizures initially recorded on a single electrode, posing a substantial diagnostic challenge. This delay in recognizing the seizures highlights the importance of careful EEG interpretation, especially in cases of unusual or subtle findings, to ensure timely diagnosis and treatment. We suggest using EEG arrays with a higher number of electrodes to improve spatial resolution or incorporating neuroimaging for correlation in such challenging cases.
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